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diff --git a/third_party/libwebrtc/common_audio/wav_header.h b/third_party/libwebrtc/common_audio/wav_header.h
new file mode 100644
index 0000000000..2cccd7d34b
--- /dev/null
+++ b/third_party/libwebrtc/common_audio/wav_header.h
@@ -0,0 +1,90 @@
+/*
+ *  Copyright (c) 2014 The WebRTC project authors. All Rights Reserved.
+ *
+ *  Use of this source code is governed by a BSD-style license
+ *  that can be found in the LICENSE file in the root of the source
+ *  tree. An additional intellectual property rights grant can be found
+ *  in the file PATENTS.  All contributing project authors may
+ *  be found in the AUTHORS file in the root of the source tree.
+ */
+
+#ifndef COMMON_AUDIO_WAV_HEADER_H_
+#define COMMON_AUDIO_WAV_HEADER_H_
+
+#include <stddef.h>
+#include <stdint.h>
+#include <algorithm>
+
+#include "rtc_base/checks.h"
+
+namespace webrtc {
+
+// Interface providing header reading functionality.
+class WavHeaderReader {
+ public:
+  // Returns the number of bytes read.
+  virtual size_t Read(void* buf, size_t num_bytes) = 0;
+  virtual bool SeekForward(uint32_t num_bytes) = 0;
+  virtual ~WavHeaderReader() = default;
+  virtual int64_t GetPosition() = 0;
+};
+
+// Possible WAV formats.
+enum class WavFormat {
+  kWavFormatPcm = 1,        // PCM, each sample of size bytes_per_sample.
+  kWavFormatIeeeFloat = 3,  // IEEE float.
+  kWavFormatALaw = 6,       // 8-bit ITU-T G.711 A-law.
+  kWavFormatMuLaw = 7,      // 8-bit ITU-T G.711 mu-law.
+};
+
+// Header sizes for supported WAV formats.
+constexpr size_t kPcmWavHeaderSize = 44;
+constexpr size_t kIeeeFloatWavHeaderSize = 58;
+
+// Returns the size of the WAV header for the specified format.
+constexpr size_t WavHeaderSize(WavFormat format) {
+  if (format == WavFormat::kWavFormatPcm) {
+    return kPcmWavHeaderSize;
+  }
+  RTC_CHECK_EQ(format, WavFormat::kWavFormatIeeeFloat);
+  return kIeeeFloatWavHeaderSize;
+}
+
+// Returns the maximum size of the supported WAV formats.
+constexpr size_t MaxWavHeaderSize() {
+  return std::max(WavHeaderSize(WavFormat::kWavFormatPcm),
+                  WavHeaderSize(WavFormat::kWavFormatIeeeFloat));
+}
+
+// Return true if the given parameters will make a well-formed WAV header.
+bool CheckWavParameters(size_t num_channels,
+                        int sample_rate,
+                        WavFormat format,
+                        size_t num_samples);
+
+// Write a kWavHeaderSize bytes long WAV header to buf. The payload that
+// follows the header is supposed to have the specified number of interleaved
+// channels and contain the specified total number of samples of the specified
+// type. The size of the header is returned in header_size. CHECKs the input
+// parameters for validity.
+void WriteWavHeader(size_t num_channels,
+                    int sample_rate,
+                    WavFormat format,
+                    size_t num_samples,
+                    uint8_t* buf,
+                    size_t* header_size);
+
+// Read a WAV header from an implemented WavHeaderReader and parse the values
+// into the provided output parameters. WavHeaderReader is used because the
+// header can be variably sized. Returns false if the header is invalid.
+bool ReadWavHeader(WavHeaderReader* readable,
+                   size_t* num_channels,
+                   int* sample_rate,
+                   WavFormat* format,
+                   size_t* bytes_per_sample,
+                   size_t* num_samples,
+                   int64_t* data_start_pos);
+
+}  // namespace webrtc
+
+#endif  // COMMON_AUDIO_WAV_HEADER_H_